They could see smoke in the distance, perhaps a mile away.
But then the smoke -- and the flames -- started to get closer.
"To our left, it was like a spark and then five minutes later the freeway was engulfed," she said.
As the flames neared they jumped I-15.
Police had come by, calling over their loudspeakers for people to stay in their cars.
Sclafani and her teammates ditched their van, left everything and started running up the mountain in the 95 degree heat of the California afternoon.
What seemed like 1,000 people were doing the same, she said.
"Including a pregnant woman we helped out," she said
They stayed up on the hill for about three hours.
"There were lots of people crying. Some were vomiting. People were really frightened," she said.
Long line of destruction
About 20 cars and trucks in a long line of abandoned vehicles on the freeway tourists use as the main road between Las Vegas and Los Angeles caught fire as flames from a brush fire jumped the highway Friday.
There were no reports of injuries, said Steve Carapia of the California Highway Patrol. He estimated there were up to 70 cars, trucks and tractor-trailers on I-15 northbound near San Bernardino.
Twenty vehicles were destroyed and 10 were damaged, San Bernardino County Fire said on its Twitter feed.
Five homes were burned and about 50 more buildings were threatened, the department said.
"You could see the flames moving from the west side of the I-15 freeway, and basically we just watched it as it literally jumped over the freeway and started the fire on the other side. And it just got worse from there," Ryan McEachron told CNN's "Anderson Cooper 360˚"
He said southbound traffic also had stopped and suddenly a huge group of people came walking up the road.
"At which point everybody on the freeway just started turning their vehicles around," he said.
As the fire headed north toward the town of Phelan, dozens of fire trucks moved into position as homeowners with garden hoses cast eerie silhouettes against the dark smoke.
Several residents were watering down their roofs and trees, knowing the flames could soon be there.
Helicopters streaked through the air, carrying huge buckets of water. Earlier they dumped their loads on burning cars, now they tried to stop the advance of the flames, burning the chaparral on the hillsides.
Video shot from helicopters over the blaze showed several cars and a tractor-trailer on fire. A boat on a trailer was also ablaze. Helicopters dumped water on some of the vehicles.
Several DC-10s also joined the battle against the fire.
For a while, officials were concerned about private drones in the airspace where they wanted to conduct drops.
"Please stop flying hobby drones in the area. We can't risk the choppers colliding with them. We could have loss of life," U.S. Forest Service spokeswoman Gerrelaine Alcordo said.
Officials with the San Bernardino National Forest said the quickly spreading brush fire in the Cajon Pass had grown to 3,500 acres in four hours.
Initially reports had the fire at 25 to 30 acres. An hour later it was 500, then another hour passed and it was 2,000.
About 200 firefighters are involved in the incident.
It was 95 degrees Friday afternoon with winds to the south at 20 mph.